In Greek mythology Erebus (Έρεβος Erebos, "Desert" from eremos ) was a primordial god, the personification of darkness and shadow, which filled in all the corners and crannies of the world. He was the offspring of Chaos alone. He was brother of Nyx and father with her of Aether and Hemera, according to Hesiod.
According to some later legends, Erebus was part of Hades, the underworld. It was where the dead had to pass immediately after dying. After Charon ferried them across the river Acheron, they entered Tartarus, the underworld proper. Erebus was often used as a synonym for Hades, the Greek god of the underworld. Also, Erebus was the name of the gloomy space through which souls passed on their way to Hades.